Evaluation of the Effects of Using 3d-Patient Specific Models of Displaced Intra-Articular Calcaneal Fractures in Surgery

SLR - June 2021 - Daniele Cole

Reference: Ozturk AM, Ozer MA, Suer O, Derin O, Govsa F, Aktuglu K. Evaluation of the Effects of Using 3d-Patient Specific Models of Displaced Intra-Articular Calcaneal Fractures in Surgery. Injury. 2020 May 13:S0020-1383(20)30402-2. doi: 10.1016/j.injury.2020.04.057. 

Level of Evidence: Level III

Scientific Literature Review

Reviewed By: Daniele Cole, DPM
Residency Program: MetroWest Medical Center – Framingham, MA

Podiatric Relevance: Calcaneal fractures result from a high-impact injury and often have displaced and intra-articular fracture patterns. Open-reduction and internal-fixation is required to realign the joint surfaces. X-ray and CT imaging can be useful in pre-operative planning, but they typically allow evaluation of the fractures in a one- or two-dimensional screen. The use of calcaneal fracture 3D models can provide personalized operation plans and allow surgeons to simulate their surgical plan beforehand. The aim of this study is to compare conventional calcaneal ORIF surgery and surgery assisted by 3D-printed models in the treatment of calcaneal fractures. 

Methods: Thirty-seven eligible patients with unilateral calcaneal fractures were randomly assigned into one of two groups: the conventional surgery group (19 cases), and the 3D model-assisted surgery group (18 cases). CT imaging was taken of all patients. In the conventional group, standard surgical calcaneal ORIF procedure was followed using plate and screw fixation. In the 3D model group, a 3D reproduction of the fractured calcaneus and a mirror image model of the contralateral calcaneus were made. Both of these models were made via 3D printing from the CT images. The surgical team could simulate ORIF procedures on the models, as well as determine plate and screw size preoperatively. All operations were performed by the same surgeon.      

Results: The operative time was significantly shorter in the 3D model group compared to the conventional group (83 +/- 4.6 minutes versus 130 +/- 5.6 minutes). There was significantly less blood loss, and significantly less fluoroscopy usage in the 3D model group. In addition, the 3D model group had significantly less time of instrumentation. Fracture union time was not statistically different between the 3D model and the conventional groups. Gissane angle and calcaneal facet height were significantly restored better in the 3D model group. There was no statistical difference of AOFAS scores between groups.  

Conclusions: The use of 3D printed models of the fractured calcaneus for ORIF procedures may be a beneficial tool to the surgeon. It provides better visualization of the fracture patterns compared to plain CT and allows for pre-operative planning and practice with plate and screw placement. However, 3D bone models would not be useful for the soft tissue dissection of a calcaneal ORIF and for emergent calcaneal fractures, there would not be sufficient time to create a model. Limitations to this study include the small sample size. Overall, this study observed shorter operative times, less blood loss, and less intra-op fluoroscopy in the 3D model group compared to the conventional group.